Power transmitting joint arrangement

ABSTRACT

A spider used in a power transmitting joint has a plurality of projecting trunnions that each receive a cup-shaped bearing capable of rotational movement relative thereto. An integral resilient means has end surface sealing means surrounding each trunnion and in sealing contact with the surface of the end of each bearing proximate the spider while allowing relative rotational movement between each bearing and trunnion.

United States Patent 1191 McElwain Dec. 11, 1973 POWER TRANSMITTINGJOINT 3,481,159 12/1969 Kayser 64/17 A ARRANGEMENT 2,629,992 3/1953Anderson... 64/17 A 3,218,692 11/1965 Kayser 64/17 A [75] lnventor: JohnC. McElwain, Rochester, V

' Primary ExaminerCharles J. Myhre [73] Assignee: Rockwell InternationalCorporation, Assistant Examiner-Randall Healld Pittsburgh, Pa.Attorney--John R. Bronaugh et a1.

[22] Filed: Aug. 12, 1971 21 Appl. No.: 171,239 [57] ABSTRACT A spiderused in a power transmitting joint has a plu- [52] U S CL 64/17 A ralityof projecting trunnions that each receive a cup- Shaped bearing capableof rotational movement rela [51] Int. Cl. Fl6d 3/26 [58] Field of SearchI 64/17 R 17 A 17 S tive thereto. An mtegral res111ent means has endsur- 64/18 face sealing means surrounding each trunnion and in sealingcontact with the surface of the end of each [56] References Citedbearing proximate the spider while allowing relative UNITED STATESPATENTS rotational movement between each bearing and trunnion.

3,174,813 3/1965 Selz 64/17 A 3,470,711 10/1969 Kayser 64/17 A 1 Claim,5 Drawing lFignres PAIENIEDBEBI 1 ma I 3.777, 510

INIVENTOR John C. McElwuin 1 POWER TRANSMITTING JOINT ARRANGEMENTBACKGROUND AND OBJECTS OF THE INVENTION Thisinvention relates to powertransmitting joints .wherein sealing contact is desired between jointmem- .of which rotatably mountcup-shaped bearings. Usually, thesecup-shaped bearings are connected to the joint yokes and movewith theyokes relativeto the center cross trunnions. To facilitate this movementeach bearing has an internal surface which is lubricated to assurefreerotation relative to a trunnion surface. For trouble free jointoperation, it is desirable to seal the interface between each internalbearing surface and corresponding trunnion to prevent the entry; of dirtand contaminents usually presentin the environmentof the joint. I

In the prior art, it is known to provide a sealing washer surroundingeach trunnionand contacting the inner end of the cup bearing to retainthe lubricant therein andto protect against the entry of dirtand othermatter from the outside. Such a washer ispositioned by a washer.seatmachined about-each trunnion on the body of the. centercross. Anexample of-such an expedientis in UJS. Pat. No. 2,916,896, entitledUniversal Joint and issued to Miller on Dec. 15, 1959, disclosingsealing rings made of a resilient material and having an annular lipwhichcontacts the inner end of the bearing. In assembling a universaljointas taught by Miller, it is necessary to individually mount eachsealing ring on each trunnion by a manual mountingstep.

It is an object of this invention to provide a novel sealing meansthatis a one-piece, resilient sealing member havingplural sealing means andcapable of being machinemolded about the cross portion of afourtrunnionspider. A major advantage of such an integral sealing member is that itcan be accurately and inexpensively machine molded about a spiderfasterthan the slower and cumbersome manual method of individually mountingfour sealing rings. In addition, this invention eliminates the need tomachine sealing washer seats on the joint spider.

It is a further object of this invention to provide an improvedsealingmember having two endless sealing projections or lips contactingeach bearing and effectively preventing access of foreign matter to thebearing surface.

Another object of the invention is to provide a sealing member thatisheld in position against possible outward movement caused by centrifugalforces arising during joint operation. By thus preventing movement ofthe sealing member proper sealing contact is maintained.

SUMMARY OF THE INVENTION A spider used in a power transmitting joint hasa pluralityof projecting trunnions which each receive a cupshapedbearing capable of rotational movement relative thereto. Anintegralresilient means has end surface sealing means surrounding eachtrunnion and in sealing contact with the surface of the end of eachbearing proximate the spider whileallowing relative rotational movementbetween eachbearing and trunnion.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a elevation view of a universaljoint trunnion spider and bearing arrangement of this invention with onecup bearing in an exploded position;

FIG. 2 is an end view taken along the line 22 of FIG. .1; j FIG. 3 is asection view taken along line 3-3 of FIG. 1;

FIG. 4 is a section view taken along the line 44 of FIG. 2; and

FIG. 5 is an enlarged detail view of a portion of FIG. 4.

DESCRIPTION OF THE INVENTION Referring to the drawings, a universaljoint center cross or trunnion spider 10 carries a plurality ofcupshaped bearings 12 which are end rotatably mounted on the end of oneof the spider trunnions 14. Portions 15 of the outer surfaces of thetrunnions are machined to a close tolerance dimension to cooperate withthe similarly machined interior surfaces 16 of the bearings to provide asuitable bearing interface; Bearings 12 are adapted to be conventionallyconnected to apertured yoke bifurcations (not shown) attached torotating members such as drive shafts. As is conventional, thisarrangement allows pivotal movement in transverse planes of the rotatingmembers for universal movement. The spider 10 is formed from a fourarmedforging.

A one-piece sealing member 17 is molded on the spider 10, and completelyencapsulates the main body portion 18 of the spider. Neoprene has beenfound to be satisfactory resilient elastomeric material from which themember .17 can be formed. Other suitable synthetics or rubber havingsuitable characteristics of flexibility and elasticity for sealingpurposes may also be used. lntegrally formed on each end of each of thesurfaces of sealing member 17 that surround the trunnions is a pair ofendless inner and outer sealing projections 20 and 22. These projectionsare shaped as radially spaced, concentric, annular tapered lips. Thesealing projections are located between the portion 18 and the end ofeach trunnion 14.

The endof each bearing 12 proximate the spider has a frusto-conicalouter surface 26 and an adjacent annular flat end surface 28. As shownin FIGS. 4 and 5, each outer tapered projection 22 is in sealing contactwith a frusto-conical surface 26, while each inner tapered projection 20is in sealing contact with an end surface 28. Because the sealingprojections 20 and 22 are resilient, slight axial movement of the cuppedbearings will not break the sealing contact. This arrangement allows thesealing contact to be maintained while allowing relative rotationalmovement between associated bearings and trunnions. Inner sealingprojections 20 limit axial movement of the bearings towards portion 18and thus aid in the axial positioning of the bearings.

The double sealing projections additionally retain lubricantplacedwithin bearings 12 to lubricate the interface between surfaces 15 and 16and also prevent dirt and other foreignmatter from contacting trunnions14. Since sealingmember 17 is an integral molded piece which surroundsthe portion 18, centrifugal forces arising during universaljointoperation are unable to cause it to move relative to the spider.Thus sealing contact is maintained as axial movement of the sealingmember along the trunnions is not possible.

It should be understood that the integral sealing member 17 is notlimited to use with a universal joint, but also may be used with anytype power transmitting joint where resilient sealing contact is desiredbetween relatively rotatable members.

It thus may be seen that this invention provides in a universal jointarrangement for the establishment of a seal to protect the cupbearing-trunnion interface by means of a one-piece, molded sealingmember formed about the center portion of the spider. Inclusion of sucha member eliminates the need for discrete sealing washers and theattendant manual task of assembling each of the washers on the spider.Also, the need for machined washer seats on the spider is eliminated. Inaddition, this arrangement serves to aid in the maintenance of thedesired seals since the integral sealing member positively is locatedand movement of this member relative to the spider prevented.

It is to be understood that the above detailed description of thepresent invention is intended to disclose an embodiment thereof to thoseskilled in the art, but that the invention is not to be construed aslimited in its application to the details of construction andarrangement of parts illustated in the accompanying drawings, since theinvention is capable of being practiced and carried out in various wayswithout departing from the spirit of the invention. The language used inthe specification relating to the operation and function of the elementsof the invention is employed for purposes of description and not oflimitation, and is not intended to limit the scope of the followingclaims beyond the requirements of the prior art.

What is claimed is:

1. In a power transmitting joint, a spider having a plurallity ofprojecting trunnions, a cup-shaped bearing receiving each trunnion andcapable of rotational movement relative thereto, each bearing having aflat open end surface, a generally cylindrical radially outermostsurface and a frusto-conical outer surface terminating at one of itsextremities at said cylindrical surface and at the other of itsextremities at said open end surface, and an integral resilient meanssurrounding each of said trunnions along a portion of the length of eachof said trunnions and terminating part way along each of said trunnionsin end surface sealing means in sealing contact with each of saidbearings, said sealing means including radially spaced apart annularinner and outer sealing lips projecting from said resilient means andintegral therewith, each of said inner lips abutting and deformedagainst a bearing flat end surface and each of said outer lips abuttingand deformed against a frustoconical outer surface.

1. In a power transmitting joint, a spider having a plurallity ofprojecting trunnions, a cup-shaped bearing receiving each trunnion andcapable of rotational movement relative thereto, each bearing having aflat open end surface, a generally cylindrical radially outermostsurface and a frusto-conical outer surface terminating at one of itsextremities at said cylindrical surface and at the other of itsextremities at said open end surface, and an integral resilient meanssurrounding each of said trunnions along a portion of the length of eachof said trunnions and terminating part way along each of said trunnionsin end surface sealing means in sealing contact with each of saidbearings, said sealing means including radially spaced apart annularinner and outer sealing lips projecting from said resilient means andintegral therewith, each of said inner lips abutting and deformedagainst a bearing flat end surface and each of said outer lips abuttingand deformed against a frusto-conical outer surface.